Undoubtedly, the process of selecting projects in organizations will not have the expected effectiveness without adopting a strategic approach. Nowadays, this has become a serious challenge to project-based organizations. In this regard, the use of the project-portfolio management approach has been suggested as an efficient tool whose use is increasing. This approach can lead to better strategic alignment, increase the success rate of projects and optimal use of the resources of the organization. So far, many studies have been done on the description of the basics of project portfolio management, but none of them has tackled the issue of the review of the problems in the absence of the establishment of this system in the organization. Thus, the present study, whose main tool is structured interview with a sample of project management experts of a country, is dedicated to this topic and explains the necessity of establishing this system based on the concepts of the dynamical approach of the system. The most important finding was the identification of 11 basic problems caused by the lack of a management system of project portfolio divided into its functional areas and its implications. Moreover, the dynamics of the relationship between the problems and their consequences and their impact on the dimensions of the organization's business performance were explained. Finally, some solutions were proposed to prevent these problems.